Protonation-triggered self-assembly of chiral copper nanoclusters: Chirality transfer and circularly polarized luminescence generation

Abstract

Complex biological processes are inseparable from the transmission of chiral information, and the realization of chiral transfer in the process of designing and manufacturing chiral functional materials is conducive to explore sophisticated nature activities. The construction of chiral nanomaterials using self-assembly strategy can effectively constitute asymmetric molecular stacking pattern and occur hierarchical chirality transfer, but there are few studies on the chirality modulation or amplification of metal nanoclusters in self-assembled systems. Herein, we select a chiral glutathione-stabilized copper nanocluster (R-GSH-Cu NCs) as the chiral donor and introduced achiral cationic polymer poly (allylamine hydrochloride) (PAH) to self assembly to form R-GSH-Cu NCs/PAH nanoaggregates. Through thesynergistic effectof hydrogen bonding and electrostatic interaction. Through the synergistic effect of hydrogen bonding and electrostatic interaction, the optical properties of nanoaggregates were greatly regulated, especially in the supramolecular chirality and circularly polarized luminescence (CPL). Meanwhile, the addition of external proton source (hydrochloric acid, HCl) into the R-GSH-Cu NCs/PAH complexes increased the protonation degree of PAH, resulting in chiral inversion and CPL amplification. Regulating chiral properties of chiral metal NCs provides a nanoscale platform for understanding chiral transfer at organic–inorganic interface, which provided candidate in 3D display, biological probes, encrypted information transmission.